## Archive for November, 2018

### What Number Do You Hate?

In 2014, Alex Bellos conducted a poll to find out people’s favorite number. Based on those results, Maddy Fry wrote an article for *Time* in which she stated,

The least favorite number turned out to be 110, which was the lowest number to receive no votes.

That’s not quite true. It would be correct to say that 110 was the *least common* favorite number, but calling it the “least favorite number” makes it sound like it’s the number that folks like least. In a poll where folks were asked to choose just one favorite number, a number that gets no votes doesn’t make it the least liked number. It just means that no one picked it as their favorite. That’s a subtle but important distinction.

It could be the case — however unlikely — that even though no one picked 110 as their favorite number, it could be everyone’s *second-favorite* number.

On the other hand, I **do** have a least favorite number.

More than two decades ago, I heard a local Maryland band called Dead City Radio (not to be confused with the song *Dead City Radio* by Rob Zombie), and I bought their debut album. Although the band is now defunct, the image from that album cover holds a permanent spot in my psyche:

The cover includes disturbing imagery of a doll, a gun, graffiti, an atomic bomb explosion, and the number 219 on the door. Why 219? I spoke with DCR’s lead singer after the show, and he told me that it was serial killer Jeffrey Dahmer‘s apartment number. *Disturbing.*

As it turns out, that’s not true. Dahmer’s apartment number in Milwaukee was actually 213, though he did meet several of his victims at Club 219. I’m not sure if the DCR guys had it wrong, or if I misheard because my ears were still ringing after the concert, or if there’s some other explanation.

Regardless, I had no reason to question the statement when I first heard it, and I now have a fear and abnormal hatred of the number 219. It’s been my least favorite number for years. I obviously avoid room 219 when I stay at hotels. (And now that I know the truth, I avoid room 213, too. In fact, I try to avoid the second floor entirely. I don’t even want to walk past those rooms.)

But my hatred is deeper than just avoiding hotel rooms. When I score 219 points playing Dots, or when I receive $2.19 in change at the grocery store, or when my GPS tells me to turn right onto Route 219, a slight shiver runs down my spine.

I’m not the only person who despises a particular number. At The Top Tens, many people say they hate many numbers for a variety of reasons:

- 6 looks weird.
- 16 is so obnoxious. I can’t stand this stupid swagger of an integer. It should burn in hell.
- 12 will lead to endless controversies.
- 18 sucks because it’s when you have to say goodbye to your childhood.
- 39 is a multiple of 13… plus it’s so annoying.

**So, what number do you hate?** Complete the poll below. (And if it isn’t working for you, jump over to **this Google poll**.) Once I get a reasonable number of responses, I’ll clean the data and share the results. Check back in early 2019.

### Our Weigh or the Highway

On the outskirts of Paris, in a triple-sealed chamber, sits a golf-ball sized cylinder made of platinum and iridium. It’s officially known as the International Prototype of the Kilogram — or IPK, for short — but locals refer to it as *Le Grand K*.

Cast in 1879, the IPK serves as the international standard for mass. For a century-and-a-half, the accuracy of any weight measurement was linked to this very precisely hewn hunk of metal.

The kilogram is the only unit still defined in terms of a manufactured object, and that’s shaky and solitary ground on which to rest. In 1960, the only other SI unit still based on a physical artifact — the meter — was redefined in terms of the wavelength of light from a specified source, linking it to natural phenomena.

But no longer.

Today, Le Grand K will be retired when representatives from 60 countries will meet in Versailles to approve a new definition of the kilogram. Officially, the change won’t take place until May 20, 2019, which means that for a short time, the IPK, Pete Sessions, and Claire McCaskill will occupy a similar state of lame-duck limbo.

And what is the new definition for the kilogram? It’s pretty straightforward…

The kilogram (kg) will be defined by taking the fixed value of the Planck constant

hto be 6.626 070 15 × 10^{−34}J⋅s. The unit J⋅s is joule-seconds, which is equal to kg⋅m^{2}⋅s^{−1}, where the meter and second are defined in terms ofc, the speed of light, which is 299,792,458 meters per second (m⋅s^{−1}), and Δν_{Cs}, the ground state hyperfine splitting frequency of cesium-133, which is 9,192,631,770 Hz.

See? Easy peezy.

Over time, the IPK has, surprisingly, lost weight. And scientists can’t really explain why. The cylinder now weighs about 50 micrograms, or roughly the weight of an eyelash, less than it weighed in 1879. The irony, though, is that a kilogram, by definition, is equal to the weight of the IPK. So, technically, it isn’t that the kilogram has lost weight; in truth, the rest of the world has been getting a little heavier. (Keep this factoid in your back pocket for a few days. It is perhaps the best and most scientific excuse you’ll be able to offer if you don’t like the reading on your scale around the holidays.)

All this talk of Le Système International makes me think about the many important benchmark conversions that should be part of every science curriculum:

2000 mockingbirds = 2 kilomockingbirds

10^{12} microphones = 1 megaphone

10 cards = 1 decacards

1,000 grams of wet socks = 1 literhosen

And the most important benchmark, for when you need to convert between expatriate poets and televangelists:

And finally, if you’ve read this far, a PG-13 passage from *Wild Thing* by Josh Bazell:

In metric, one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade — which is one percent of the difference between its freezing point and its boiling point. An amount of hydrogen weighing the same amount has exactly one mole of atoms in it. Whereas in the American system, the answer to “How much energy does it take to boil a room-temperature gallon of water?” is “Go fuck yourself,” because you can’t directly relate any of those quantities.

### What’s in Your Pocket?

I recently received an email from adoring fan Alden Bradford:

Teacher: “Would you like a pocket calculator?”

Student: “No, thanks. I already know how many pockets I have.”

Thanks, Alden!

Of course, that reminded me of this gem from Spiked Math:

And one final pocket joke:

The department chair said to the math teachers, “I have good news, and I have bad news. The good news is, we have enough money for a new microwave in the staff lounge.” The teachers cheered! Then one of them asked, “What’s the bad news?” The chair said, “It’s still in your pockets.”

Ouch.

### No Bull — This is My New Favorite Fermi Question

It’s hard to say which emotion was strongest — awe, bewilderment, admiration, horror, fear — when I heard the following statistic:

McDonald’s sells 75 hamburgers every second.

But I’m a math guy, so there’s no doubt where my mind turned after that emotion passed:

How many cows is that?

Have at it, internet.

What do you get when you divide the circumference of a bovine by its diameter?

Cow pi.What is the favorite course at Bovine College?

Cowculus.A mathematician counted 196 cows in the field. But when he rounded them up, he got 200.